<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>使用类选择器画盒子</title>
		<style>
			.red{
				width: 100px;
				height: 100px;
				/*背景颜色*/
				background-color:red;
			}
			.green{
				width: 100px;
				height: 100px;
				/*背景颜色*/
				background-color:green;
			}
		</style>
	</head>
	<body>
		<div class="red">11</div>
		<div class="green">22</div>
		<div class="red">33</div>
	</body>
</html>
